1. Frequency ( 1)
2. Echoes (1)
3. spread out, same as or equal to (2)
b) The vibrations are parallel to the direction of energy transfer (2)
4. Expensive as long wires are needed to go around the mountains to reach the home (1)

10. The lower the cost, the more efficient it is because:
- Huge difference between e.g panel C and panel A only for an extra 10% efficiency (1)
- (Numerical evidence) 8 Panel Cs will total up to £44 with 80% efficiency (1)

11. why france will still use nuclear power(2) :
- cost of electricity is cheaper with Nuclear than with renewable sources
- produces much more electricity than it actually needs using nuclear power
- produces no greenhouse gases like co2

13. factors that affect rate of energy transfer of mug(2):
-room temperature so larger difference in temperature of mug and surroundings
-surface area of mug

b) How does energy pass from the mug base?
-Conduction, particles gain kinetic energy and collide more frequently,
-passing on their extra kinetic energy to other particles .(2)

c) how is a convection current formed in the mug(4):
-liquid at the bottom is heated and particles gain kinetic energy
-and move away from each other, this makes the liquid less dense
- causing it to rise
-and displace the denser colder air at the top , the denser particles then fall
-heated again (creating a circulation with is convection currents)

14) control variable for the investigation measuring rate of evaporation (1) :
-same beaker
-same type of beaker
-same position in the room
- same thermometer
- To tear the data logger to zero for all three

(Original post by Hahahqjaj)
You know the question about the properties of microwave and infrared. Is there any chance of getting a mark for saying

Same wavelength

Same frequency

Idk why I put that when I new the other answer 😒

Thanks

Not sure i'm a afriad because microwaves have higher wavelengths than infrared and microwaves have lower frequencies than infrared too sorry
But i lost loads of marks throughout the paper too a lot of us did, don't worry!

(Original post by CaSama9)
it was that one where you had to use the equation
v = f × λ
So you had something hertz
You had the wavelength
and you had to times them
it was 340m/s
am i talking about the right one lol?

(Original post by CaSama9)
it was that one where you had to use the equation
v = f × λ
So you had something hertz
You had the wavelength
and you had to times them
it was 340m/s
am i talking about the right one lol?